Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists uncover amyloid-like proteins in bacteria

09.07.2003


Independent research groups have uncovered a new class of proteins, called the chaplins, that function like amyloid fibrils to allow reproductive growth in the bacterium Streptomyces coelicolor. Amyloid proteins are most commonly recognized for their role in Alzheimer’s disease, where they aggregate into insoluble, mesh-like plaques in the brains of Alzheimer’s patients. This finding reveals an unprecedented role for amyloid-like proteins in Gram-positive bacteria.



S. coelicolor is a soil-dwelling bacterium that, along with its relatives, produces the majority of naturally derived antibiotics (e.g., tetracycline and erythromycin), as well as many antitumor, antifungal, and immunosuppressant agents. Unlike most other prokaryotes, S. coelicolor has a complex life cycle, producing two different cell types depending upon environmental conditions: vegetative substrate hyphae that grow in moist soil, and aerial hyphae that grow in air and give rise to reproductive spores.

As published in the July 15th issue of Genes & Development, independent research carried out by Dr. Marie Elliot, Dr. Mark Buttner and colleagues at the John Innes Centre (UK) and Stanford University (USA), and by Dennis Claessen, Dr. Lubbert Dijkhuizen, Dr. Han Wösten and colleagues at the University of Groningen and the University of Utrecht (Netherlands), have identified the chaplin protein family as essential mediators of aerial S. coelicolor growth. The research in the Netherlands was funded by a grant of the National Programme EET (Economy, Ecology and Technology) to find biological alternatives for the environmentally harmful antifouling compounds used today on ships.


Although the two groups used different experimental approaches to identify genes involved in aerial hyphae formation, both reached a common conclusion. Both groups discovered a previously unidentified family of hydrophobic, cell-surface proteins whose eight members (chaplins A-H) are necessary for aerial hyphae formation. In independent experiments, Elliot et al. and Claessen et al. demonstrated that streptomycetes lacking specific chaplin genes were unable to erect aerial hyphae, but that this condition could be restored through the application of exogenous chaplin proteins.

The authors suggest that coating of the aerial hyphae by chaplin proteins may confer hydrophobicity to these structures, allowing them to grow into the air and possibly even preventing back-growth into the moist soil. "The hydrophobic nature of aerial structures could be an ideal property to prevent organisms from fouling in shipping. In our aim to find biological alternatives for antifouling compounds we are currently studying the antifouling properties of these highly surface active proteins," explains Dennis Claessen, of the University of Groningen.

Dr. Dijkhuizen’s group further investigated the role of the chaplin proteins at the soil/air interface, finding that chaplin genes E and H are also expressed in the submerged substrate hyphae. The researchers went on to show that a mixture of chaplin proteins D - H self-assembled into amyloid-like fibrils at the soil/air interface, suggesting that chaplins D-H may help lower the water surface tension to facilitate the breakthrough of aerial structures into air.

The identification of the chaplin proteins in Streptomyces potentially has important implications for its use by the pharmaceutical industry. "Chaplins adopt an amyoid-like structure, and could therefore be used as a model system to find molecules that prevent formation of amyloid fibrils" said Dennis Claessen and Dr. Marie Elliot. Furthermore, this landmark discovery of functional amyloid-like fibrils in Gram-positive bacteria illustrates the diversity of amyloid function across genomes.

Heather Cosel | EurekAlert!

More articles from Life Sciences:

nachricht TU Bergakademie Freiberg researches virus inhibitors from the sea
27.03.2020 | Technische Universität Bergakademie Freiberg

nachricht The Venus flytrap effect: new study shows progress in immune proteins research
27.03.2020 | Jacobs University Bremen gGmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Junior scientists at the University of Rostock invent a funnel for light

Together with their colleagues from the University of Würzburg, physicists from the group of Professor Alexander Szameit at the University of Rostock have devised a “funnel” for photons. Their discovery was recently published in the renowned journal Science and holds great promise for novel ultra-sensitive detectors as well as innovative applications in telecommunications and information processing.

The quantum-optical properties of light and its interaction with matter has fascinated the Rostock professor Alexander Szameit since College.

Im Focus: Stem Cells and Nerves Interact in Tissue Regeneration and Cancer Progression

Researchers at the University of Zurich show that different stem cell populations are innervated in distinct ways. Innervation may therefore be crucial for proper tissue regeneration. They also demonstrate that cancer stem cells likewise establish contacts with nerves. Targeting tumour innervation could thus lead to new cancer therapies.

Stem cells can generate a variety of specific tissues and are increasingly used for clinical applications such as the replacement of bone or cartilage....

Im Focus: Artificial solid fog material creates pleasant laser light

An international research team led by Kiel University develops an extremely porous material made of "white graphene" for new laser light applications

With a porosity of 99.99 %, it consists practically only of air, making it one of the lightest materials in the world: Aerobornitride is the name of the...

Im Focus: Cross-technology communication in the Internet of Things significantly simplified

Researchers at Graz University of Technology have developed a framework by which wireless devices with different radio technologies will be able to communicate directly with each other.

Whether networked vehicles that warn of traffic jams in real time, household appliances that can be operated remotely, "wearables" that monitor physical...

Im Focus: Peppered with gold

Research team presents novel transmitter for terahertz waves

Terahertz waves are becoming ever more important in science and technology. They enable us to unravel the properties of future materials, test the quality of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“4th Hybrid Materials and Structures 2020” takes place over the internet

26.03.2020 | Event News

Most significant international Learning Analytics conference will take place – fully online

23.03.2020 | Event News

MOC2020: Fraunhofer IOF organises international micro-optics conference in Jena

03.03.2020 | Event News

 
Latest News

3D printer sensors could make breath tests for diabetes possible

27.03.2020 | Power and Electrical Engineering

TU Bergakademie Freiberg researches virus inhibitors from the sea

27.03.2020 | Life Sciences

The Venus flytrap effect: new study shows progress in immune proteins research

27.03.2020 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>